speed up ExternalWikiService#get_project_wiki_path

* This method previously iterated over all services in a project.  Now it
will directly query the ExternalWikiService for the project and filter
by active state.
* The presence of an external wiki is also cached
* When an external wiki is added or removed, the cached value is updated

1 files changed, 8 insertions, 0 deletions

diff --git a/app/models/service.rb b/app/models/service.rb
index 5432f8c7ab4..4821096379c 100644
--- a/app/models/service.rb
+++ b/app/models/service.rb
@@ -17,6 +17,7 @@ class Service < ActiveRecord::Base
 
   after_commit :reset_updated_properties
   after_commit :cache_project_has_external_issue_tracker
+  after_commit :cache_project_has_external_wiki
 
   belongs_to :project, inverse_of: :services
   has_one :service_hook
@@ -25,6 +26,7 @@ class Service < ActiveRecord::Base
 
   scope :visible, -> { where.not(type: ['GitlabIssueTrackerService', 'GitlabCiService']) }
   scope :issue_trackers, -> { where(category: 'issue_tracker') }
+  scope :external_wikis, -> { where(type: 'ExternalWikiService') }
   scope :active, -> { where(active: true) }
   scope :without_defaults, -> { where(default: false) }
 
@@ -212,4 +214,10 @@ class Service < ActiveRecord::Base
       project.cache_has_external_issue_tracker
     end
   end
+
+  def cache_project_has_external_wiki
+    if project && !project.destroyed?
+      project.cache_has_external_wiki
+    end
+  end
 end